03
Feb
Study Adds to Growing Body of Research Linking Common Lung Disease (COPD) to Work-Related Pesticide Exposure
(Beyond Pesticides, February 3, 2022) A study published in the journal Thorax finds lifetime occupational (work-related) exposure to pesticides increases incidents of chronic obstructive pulmonary disease (COPD), including emphysema and chronic bronchitis. Although research often attributes COPD risk to genetics or cigarette smoking, the increasing rate of COPD incidents indicates an external cause of disease development. Although an exact etiology (cause) of the increase in respiratory disease cases remains unknown, the connection between chronic respiratory diseases and exposure to pesticides continues to strengthen. Several circumstances, including smoking patterns, poverty, occupation, and diet, can influence disease prognosis. However, studies show that relative exposure to chemicals like pesticides can occur within each circumstance, making chemical exposure ubiquitous. Additionally, pesticide drift is an omnipresent issue impacting communities surrounding farming operations, and dust may harm humans, plants, and aquatic systems. Therefore, this review highlights the significance of evaluating the association between pesticide exposure and disease development, especially for diseases generally attributed to genetics or vices. Researchers in the study note, “[W]e found that cumulative exposure to pesticides is associated with an increased risk of COPD, with positive exposure-response trends. The unique large sample and the confirmation of our results in sensitivity analyses, in particular in never-smokers, support the validity of these findings and deserve further investigation.”
The respiratory system is essential to human survival, regulating gas exchange (oxygen-carbon dioxide) in the body to balance acid and base tissue cells for normal function. However, damage to the respiratory system can cause many issues—from asthma and bronchitis to oxidative stress that triggers the development of extra-respiratory manifestations like rheumatoid arthritis and cardiovascular disease. Many researchers, including those in this study, suggest an increase in environmental pollutants like pesticides may be responsible for the influx of respiratory diseases.
Using the UK Biobank, researchers collected data on age, sex, lifetime smoking history, current employment, and doctor-diagnosed asthma through a baseline questionnaire. The researchers employed the ALOHA(+)job-exposure matrix (JEM) that used an assessment by industrial hygienist experts to evaluate the occupational hazards for COPD in community-based studies. After completing the baseline questionnaire, participants underwent lung function testing. Researchers mainly relied on data from participants who never smoked or had asthma. Overall, the study confirms that pesticide exposure plays a role in COPD risk, especially for occupations with high cumulative exposure, including agriculture, fishing, gardening, and ground/park keeping. The association between pesticides and COPD is stronger among individuals who never smoked and who have no history of asthma.
The connection between pesticides and associated respiratory risks is nothing new. Although this study does not specify which pesticides increase respiratory risk, previous research demonstrates acetylcholinesterase inhibiting (AChE) pesticides (i.e., organophosphates and carbamates) can have the most influence on disease development. These chemicals bind to receptor sites for the enzyme acetylcholinesterase, which is essential in nerve impulse transmission. The inactivation of AChE through binding prevents the clearing of acetylcholine. The buildup of acetylcholine can lead to acute impacts, such as uncontrolled, rapid twitching of some muscles, paralyzed breathing, convulsions, and, in extreme cases, death. The compromise of neural transmission can have broad systemic impacts on the function of multiple body systems. Even exposure to fumigants, such as methyl bromide, can cause respiratory manifestations (e.g., dyspnea, cough, respiratory irritation, and pulmonary lesions) in conjunction with local or systemic systems like fatigue, headache, dizziness, vomiting, abdominal pain, seizures, and impairment of the function of other organs. However, individuals can still encounter pesticides outside of the work environment via pesticide drift or contamination. Communities adjacent to chemical-intensive farms or pesticide manufacturing plants experience higher levels of pesticide exposure than neighborhoods that are not. Furthermore, children living in homes near greenhouses that use these insecticides have abnormal nervous system function, including adverse pulmonary effects like asthma. Similar to asthma, COPD has the potential to cause disparities in morbidity and mortality that disproportionately impact low-income populations, people of color, and children living in inner cities.
This study adds to the growing body of research demonstrating workplace or occupational exposure to pesticides increases COPD risk. Participants’ risk of COPD increased by 13 percent when accounting for cumulative exposure, with extensive, high concentrations of pesticide exposure resulting in a 32 percent increase in disease risk. Besides COPD, other common respiratory manifestations associated with occupational pesticide exposure are dyspnea and coughing, with coughing significantly higher among agricultural workers than nonagricultural. Although individuals working in the agricultural sector have a higher risk of COPD, this study is one of the first to demonstrate increased COPD for other pesticide-intensive occupations like landscapers (i.e., gardeners/groundsmen).
In the U.S., over 14 million individuals have COPD, with the disease being the sixth leading cause of death. The increasing rate of respiratory illnesses since the 1980s demonstrates a need for better environmental policies and protocols on contaminants like pesticides. Considering respiratory diseases represent a major health issue for agricultural workers—who often experience pesticides exposure at higher rates due to occupation—it is essential to understand the association between pesticide exposure and respiratory illness, or the study of causes and effects of respiratory diseases. With reports finding associations between air pollution and higher death rates related to the outbreak of COVID-19, global leaders must eliminate toxic pesticide use to mitigate further respiratory distress on human health. Considering COVID-19 is a systemic (general) disease that overwhelmingly impacts the respiratory system of many patients, exposure to pesticides presents a heightened risk of co-occurring symptoms.
It is vital to understand how exposure to pesticides can increase the risk of developing acute and chronic respiratory problems, especially if current policies fail to decrease the persistence of toxic chemicals in the environment. Beyond Pesticides tracks the most recent studies related to pesticide exposure through our Pesticide Induced Diseases Database (PIDD). This database supports the clear need for strategic action to shift from pesticide dependency. For more information on pesticide exposure harms, see PIDD pages on asthma/respiratory effects, cancer, endocrine disruption, and other diseases. Additionally, learn how to protect yourself from COVID-19 safely by visiting Beyond Pesticides’ webpage on Disinfectants and Sanitizers for more information.
Buying, growing, and supporting organic can help eliminate the extensive use of pesticides in the environment. Organic agriculture has many health and environmental benefits, which curtail the need for chemical-intensive agricultural practices. Regenerative organic agriculture revitalizes soil health through organic carbon sequestration while reducing pests and generating a higher return than chemical-intensive agriculture. For more information on how organic is the right choice for consumers and the farmworkers who grow our food, see Beyond Pesticides webpage, Health Benefits of Organic Agriculture.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: Thorax, Health Day
